Ministers should consider scrapping grammar schools because they have fuelled social segregation between state schools, according to government research.

Allowing the 164 existing grammar schools to select according to pupils' abilities and allowing other schools - mostly faith schools - to run their own admissions system has created social divides between rich and poor, the report on school admissions said.

The research, by academics at the National Centre for Social Research and Sheffield Hallam University, and funded by the Department for Children, suggests that a new code of admissions introduced last year is likely to prevent most corrupt admissions processes. But schools that have controlled their own admissions - instead of relying on local authorities - have been more likely to covertly select. They include voluntary-aided schools, largely faith-based schools.

"Voluntary aided schools have socially segregated intakes," the report said. "Part of the explanation is that they more often use criteria and procedures that offer direct means of social selection."

It suggests that forcing faith schools to take a proportion of non-faith students would improve the situation.

It sets out options to prevent schools becoming more segregated, including stripping them of powers to run their own admissions, forcing schools to take quotas of children of different abilities, introducing lotteries at oversubscribed schools and banning any form of selection. This would effectively put an end to grammar schools and the right for most secondaries to select a small number according to aptitude in the school's specialist subject.